Have you decided on your Halloween costume yet? If you haven't already put many hours into this year's costume, you might consider a new take on the old standby: the zombie. But not your average bloody, bandaged abomination... and for the love, not a mustached, hipster kind of zombie (judging from the prevalence of random mustaches on everything from cars to duct tape, I'm going to say if this hasn't happened yet, it's a virtual inevitability)... go for the sci-fi thriller kind... the kind that results from a parasitic larva that simultaneously feasts on your innards while compelling you to do its bidding. The kind that violated this poor little katydid:

Katydid Zombie

If my Google isn't broken, it would seem this poor katydid was infected by a horsehair worm, also known as a Gordian worm for the long, torturous knots it ties itself into as an adult. The nasty little details of its life cycle are not perfectly understood, but it is clear that adults mate and lay their eggs in water. The larvae that hatch may infect hosts by developing into cysts that hang out, waiting to be ingested by an unsuspecting insect. Then when conditions are just so, (cue scary music) you can guess what happens... the little horsehair larva begins consuming its host. Then one day, Monsieur Le Worm is ready to bail; it bores a hole in its host's side and worms its way out without so much as a thanks. Whatta jerk.

Incidentally, if you are the über-nerdy type who can't resist an obscure Halloween costume and you want to take this to the next level, it might behoove you to know why the Gordian worm is so named. As it turns out, the ancient Greeks had a story they liked to tell about King Gordius of Phrygia, a farmer-turned-king who tied a knot so absurdly complicated that the oracles predicted it could only be unraveled by the next ruler of Asia. So while many hopefuls fussed and fiddled clumsily with the knot, Alexander the Great swooped in and changed the rules to his advantage. He pulled out his sword and sliced through the knot. Gordian knot unraveled? Check. Now on to rule Asia.

Alexander the Great & the Gordian Knot in plate 2 of 11 by Antonio Tempesta of Florence, 1608

So there you have it, the world's most random pairing of obscure Halloween costumes (dromroll, please!): a katydid zombie and Alexander the Great, poised to liberate said katydid from its Gordian worm. Any takers?

The views expressed are those of the author(s) and are not necessarily those of Scientific American.

ABOUT THE AUTHOR(S)

Kalliopi Monoyios

Kalliopi Monoyios is an independent science illustrator. She has illustrated several popular science books including Neil Shubin's Your Inner Fish and The Universe Within, and Jerry Coyne's Why Evolution is True. Find her at www.kalliopimonoyios.com.

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Subscribe Now!Parasite Got You Tied Up in Knots? Call in Alexander the GreatHave you decided on your Halloween costume yet? If you haven’t already put many hours into this year’s costume, you might consider a new take on the old standby: the zombie.

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